This invention relates to an apparatus for controlling the timing of ignition of an internal combustion engine.
In view of the fact that a maximum engine ouput torque is obtained when the engine crankshaft position .theta..sub.Pmax at which the cylinder pressure is at maximum is within a crankshaft angle range, for example, from about 10 degrees to about 20 degrees after top dead center, it is the conventional practice to bring the crankshaft position .theta..sub.Pmax to a target value by adjusting the engine ignition timing in a sense and direction to correct the sensed error between target and actual values for the crankshaft position .theta..sub.Pmax at which the cylinder pressure is at maximum. This is disclosed, for example, in Japanese Patent Kokai No. 58-82074.